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Chd|====================================================================
Chd|  DTNODA_STIFINT                source/interfaces/inter3d1/dtnoda_stifint.F
Chd|-- called by -----------
Chd|        INITIA                        source/elements/initia/initia.F
Chd|-- calls ---------------
Chd|        MESSAGE_MOD                   share/message_module/message_mod.F
Chd|====================================================================
      SUBROUTINE DTNODA_STIFINT( MS    ,STIFN  ,DT_STIFINT)
C-----------------------------------------------
C   M o d u l e s
C-----------------------------------------------
      USE MESSAGE_MOD
C-----------------------------------------------
C   I m p l i c i t   T y p e s
C-----------------------------------------------
#include      "implicit_f.inc"
C-----------------------------------------------
C   C o m m o n   B l o c k s
C-----------------------------------------------
#include      "com04_c.inc"
C-----------------------------------------------------------------
C   D u m m y   A r g u m e n t s
C-----------------------------------------------
      my_real , INTENT(INOUT) ::  DT_STIFINT
      my_real , INTENT(IN) ::  MS(NUMNOD) ,STIFN(NUMNOD)
C-----------------------------------------------
C   L o c a l   V a r i a b l e s
C-----------------------------------------------
      INTEGER 
     .   N
      my_real 
     .   DTNOD, DTFAC, DTN
C----------------------------------------------------------
C    Estimation Time step needed for contact stiffness computation 
C----------------------------------------------------------

        DTFAC = ZEP9
        DTNOD = EP20
        DO N=1,NUMNOD
           IF(STIFN(N)>ZERO.AND.MS(N)>ZERO)THEN 
             DTN = DTFAC*SQRT(TWO * MS(N) / STIFN(N)) 
             DTNOD = MIN(DTNOD,DTN) 
           ENDIF                      
        ENDDO
C
        DT_STIFINT = DTNOD

      RETURN
      END
